ZooKeeper: Because Coordinating Distributed Systems is a Zoo

ZooKeeper is a high-performance coordination service for
distributed applications. It exposes common services - such as
naming, configuration management, synchronization, and group
services - in a simple interface so you don't have to write them
from scratch. You can use it off-the-shelf to implement
consensus, group management, leader election, and presence
protocols. And you can build on it for your own, specific needs.

The following documents describe concepts and procedures to get
you started using ZooKeeper. If you have more questions, please
ask the mailing list or browse the
archives.